It is proposed to continue studies of experimentally induced optic nerve disease, especially the mechanisms by which elevation of intraocular pressure causes damage (in the form of cupping) to the optic nerve in glaucoma. In this project period it is proposed to concentrate on axaplasmic flow, but continuing to observe effects of pressure and ischemia on astrocytes. Methods will include autoradiography and electron microscopy. BIBLIOGRAPHIC REFERENCES: Anderson, D.R. and Davis, E.B.: Sensitivities of ocular tissue to acute pressure-induced ischemia. Arch. Ophth. 79:67-76, January 1975. Anderson, D.R.: Pathogenesis of glaucomatous cupping: A new hypothesis. In: 1974 Symposium on Gaucoma, Transactions of the New Orleans Academy of Ophthalmology. St. Louis, C.V. Mosby Co., 1975, pp. 81-94.